The Supreme Court of the United States, upon petition for a writ of certiorari, has vacated the judgment of this court, 553 F.2d 581, and remanded the case to us for further proceedings in conformity with the opinion of the Supreme Court, City of Los Angeles, Department of Water and Power, et al. v. Manhart et al., --- U.S. ----, 98 S.Ct. 1370, 55 L.Ed.2d 657, 1978. Pursuant to the mandate of the Supreme Court, it is ordered that that portion of the injunction issued by the district court which awarded a refund of all excess contributions by the plaintiffs made on or after April 5, 1972, is hereby reversed. In all other respects, the injunction issued by the district court is affirmed.